The Argentina international joined the Serie A runner-up from Real Madrid as a replacement for Edinson Cavani in July, with the Gunners failing in their attempts to sign the Argentine attacker.

Now he is set to feature against the north London club in Napoli's opening fixture of the Emirates Cup and Benitez expressed his delight at landing the striker.

"I don't know how long [he will play] but I think that he has to play because he is training well, he is fine, but we'll have to manage it at the time," the Spaniard said. "He's a great player and it was an easy decision for me [to sign him], I told the chairman that I liked the player, so the technical director and the chairman, they were quick and after we signed the player [I was] really pleased because he is a top class player."

Benitez also said he was surprised to be able to land Pepe Reina in a loan deal from Liverpool but was thrilled to acquire his services.

"Obviously, I know the situation and I was surprised, because we were trying to sign Julio Cesar," the Stadio San Paolo boss continued.

"It was a surprise for us when Pepe Reina was available, so for us it's a big boost, really important because he's a great player."